How to Make a 3.7 V Class-D Speaker Amplifier for Differential Analog Input

A class D amplifier is actually a category of amplifier through which the power devices (mosfets and BJTs) are controlled like switches.
The connected output devices in such amplifier circuits either turn fully ON or fully OFF, but never switch between other undefined levels being sure minimal heat dissipation and highest effectiveness from the devices. The functioning associated with these amplifier circuits might be known given below:
An opamp based comparator is available whose inputs are given with two signals, one is the music signal which ought to be heightened although the other is a sample high frequency triangle wave signal.
The opamp is forced to compare and evaluate the music signal with the sample triangle waves and generate an output which can be believed to be precisely proportionate as well as in tandem to the original music signal but in a PWM or a pulse width modulated form.
This music equivalent PWM is more amplified by the adjoining power mosfet or BJT stages to be able to reproduce a crystal clear music which might be a precise replica of the fed music and accomplished without much heating up of the mosfets. This enables relatively lower amps to be used than the standard form of amplifiers available other categories for example class A/B/C etc.
One such IC which is supposed to carry out a class D type of amplification is the IC BD5460 which would not even need an external choke LC filter for the procedures. Generally an inductor filter turns into important mostly with class D amplifier topologies for lessening the followed harmonics and equivalent disruptions.
The chip evolves into preferably suited to mini handheld audio devices for instance in cellphones, IPods, Ipads, FM radios etc.
The IC is stipulated with an output power of about 2 watts at 3.7V. The range of the input power could possibly be from 2.5 V to 6.5 V DC.
The IC as well likes other built-in benefits like a standby function, short circuit protection, thermal shutdown and under voltage lockout function.
A number of class D amplifier circuits making use of the IC BD5460 could be observed in this article diagrams. The left hand side design is differential input based amplifier, while the right hand side represents a single ended topology. All the 0.1uF capacitors are set up as input decoupling filters.


A lot more information regarding the IC BD BD5460 could be obtained from the following datasheet of the IC.